초록 ▼

An engine speed control system for an internal combustion engine mounted on a vehicle comprises an actuator for actuating a throttle valve for increasing and decreasing the idling speed, an ignition switch for producing a signal during the operation of the engine, an engine speed signal generating c

An engine speed control system for an internal combustion engine mounted on a vehicle comprises an actuator for actuating a throttle valve for increasing and decreasing the idling speed, an ignition switch for producing a signal during the operation of the engine, an engine speed signal generating circuit, an engine speed increasing signal generating circuit and an engine speed decreasing signal generating circuit, an actuator control circuit for operating the actuator in opposite directions in accordance with engine speed increasing and decreasing signals, a vehicle speed signal generating circuit, and an idling signal generating circuit for generating an idling signal in the idling operation of the engine. A stop switch is provided for producing a signal when the throttle valve reaches the closed position. A logic gate means is provided to be operated by the vehicle speed signal, idling signal, signal of the ignition switch and signal of the stop switch for turning off the actuator control circuit for stopping the operation of the actuator.

대표청구항 ▼

1. In a system for controlling the idling speed for an internal combustion engine mounted on a vehicle, said engine having an induction passage and a throttle valve in said induction passage, an improvement comprising: ignition switch means for producing an ignition switch signal when said igniti

1. In a system for controlling the idling speed for an internal combustion engine mounted on a vehicle, said engine having an induction passage and a throttle valve in said induction passage, an improvement comprising: ignition switch means for producing an ignition switch signal when said ignition switch means is opened; actuator means, upon occurrence of said ignition switch signal, for undergoing movement for operatively moving said throttle valve into a closed position closing said induction passage; sensing switch means for producing a closed throttle valve position signal when said throttle valve reaches said closed position; and means responsive to said closed throttle valve position signal for stopping the movement of said actuator means substantially when said throttle valve reaches said closed position, whereby movement of said actuator means is minimized and the engine is prevented from running on after the ignition switch means is opened. 2. The system according to claim 1, wherein said actuator means includes an actuating member undergoing said movement of said actuator means and for operatively moving said throttle valve. 3. The system according to claim 2, further comprising connecting means connected to said throttle valve and abutting said actuating member for moving said throttle valve operatively via said actuating member. 4. The system according to claim 3, wherein said sensing switch means comprises abutting portions of said actuating member and said connecting means, said actuator means for continuing said movement of said actuating member, when said throttle valve reaches said closed position, in a direction away from said connecting means so as to open said sensing switch means for producing said closed throttle valve position signal. 5. The system according to claim 4, further comprising spring means for biasing said connecting means against said actuating member and to move said throttle valve into said closed position. 6. The system according to claim 5, wherein said connecting means and said throttle valve form a movable unit, stopper means for stopping said unit when said throttle valve reaches said closed position, said actuating member continuing its said movement thereafter until said sensing switch means opens. 7. The system according to claim 3, wherein said sensing switch means comprises abutting portions of said actuator means and a member connected to said throttle valve, said actuator means for continuing said movement, when said throttle valve reaches said closed position, in a direction away from said member so as to open said sensing switch means for producing said closed throttle valve position signal. 8. The system according to claim 1, further comprising an engine speed signal generating circuit means for producing an engine speed signal dependent on engine speed, comparing circuit means for comparing said engine speed signal with a predetermined reference value and for producing engine speed control signals representing whether the level of said engine speed signal is higher than said predetermined reference value or not, an actuator control circuit means for operating said actuator means in the throttle valve opening direction or the throttle valve closing direction in accordance with said engine speed control signals respectively. 9. The engine speed control system according to claim 1, wherein said actuating member is a rod. 10. The engine speed control system according to claim 1, further comprising spring means for biasing said throttle valve into said closed position, said actuator means is mounted so as to counteract said spring means and such that said movement of said actuator means operatively releases said spring means moving said throttle valve into said closed position. 11. The engine speed control system according to claim 10, wherein said movement of said actuator means is retraction and said spring means biases said throttle valve so as to operatively abut against said actuator means. 12. In a system for controlling the idling speed for an internal combustion engine mounted on a vehicle, said engine having an induction passage and a throttle valve in said induction passage, wherein: said throttle valve has a closed position closing said induction passage; an actuator means having an actuating member disposed to perform movement; a lever operatively connected to said throttle valve for joint movement therewith; and means comprising a spring for biasing said lever against said actuating member so that said lever follows said actuating member of the actuator means and simultaneously said spring means via said lever for operatively biasing said throttle valve in a direction of closing the induction passage; said actuating member upon said movement for actuating said throttle valve via said lever such that said spring means closes said throttle valve; ignition switch means for producing a first signal having a first logic level during normal operation of said engine and producing an ignition switch off signal having an other logic level when the ignition switch means is opened; an idling signal generating circuit including an idling sensing switch means for generating an idling signal having a first logic level in idling operation of said engine and respectively for producing a throttle valve closed signal having an other logic level when said throttle valve reaches the closed position; and said actuator means upon occurrence of said ignition switch off signal cooperates with said lever by said movement of said actuating member in a first direction such that said throttle valve is moved via said spring means to said closed position closing said induction passage and said actuating member continues moving in said first direction, said actuating member being disposed so as to disengage from said lever by continued movement of the actuating member in said first direction substantially when the throttle valve and said lever stop at said closed position; and logic gate means responsive to said ignition switch off signal of said ignition switch means and to said idling signal of said idling signal generating circuit for producing an output for operating said actuator means so as to operate said actuating member of said actuator means to perform said movement in said first direction such that the throttle valve is moved to said closed position closing said induction passage, and said logic gate means respectively responsive to said throttle valve closed signal of said idling signal generating circuit at the closed position for stopping the movement of said actuating member of said actuator means. 13. The engine speed control system according to claim 12, wherein said idling sensing switch means is comprised between an end of said actuating member and said lever. 14. The engine speed control system according to claim 12, further comprising operating signal generating means for applying an operating signal to said actuator means via said logic gate means for said operating of said actuator means so as to operate said actuating member of said actuator means to perform said movement in said first direction such that the throttle valve is moved to said closed position closing said induction passage in response to said ignition switch off signal of said ignition switch means and to said idling signal of said idling signal generating circuit. 15. The engine speed control system according to claim 14, wherein said operating signal generating means is an oscillator. 16. The engine speed control system according to claim 12, further comprising an engine speed signal generating circuit means for producing an engine speed signal dependent on engine speed, comparing circuit means for comparing said engine speed signal with a predetermined reference value and for producing engine speed control signals representing whether the level of said engine speed signal is higher than said predetermined reference value or not, an actuator control circuit means for operating said actuator member in a second direction such that said throttle valve is moved in an opening direction relative to said induction passage or said first direction such that the throttle valve is moved in a closing direction relative to said induction passage in accordance with said engine speed control signals. 17. The engine speed control system according to claim 12 wherein said throttle valve is rotatably mounted in said induction passage, said lever comprises means for rotating said throttle valve via an end of said actuating member, said idling sensing switch is comprised between the end of said actuating member and said lever for rotating said throttle valve.